The latest Big Finish Short Trip The Shattered Hourglass is another great example of finding a whole story from a throwaway line of dialogue in a Doctor Who television episode. But I can’t say which one, as it leaves a properly big grin on your face once you realise which episode it’s taken inspiration from.

It begins at the Time Agency, the institution that Captain Jack Harkness once worked for and which has become a bit of a regular in spin-off media, where Time Marshal Helen Barnes is removing entire galaxies from existence. She is written with huge presence, and the supporting characters certainly work for her, rather than with her, at the agency.

Such powers can’t go unchecked, and the Tenth Doctor turns up to question the Time Agency’s actions, although quickly gets labelled as the pot calling the kettle black for his own time-changing antics.

Galaxy L-10, home to over a trillion beings, has a 96% chance of being an existential threat to the universe if its occupants discover time travel and that’s the rationale behind the Time Marshal’s plan to put it in a time-lock. Near-certainty of destructive potential is nowhere near enough of an excuse to condemn the galaxy with the flick of a switch, in the Doctor’s mind.

Despite being a totally standalone short trip, the crux of this story feels like it would fit right in to the recent Time Lord Victorious story arc with the exploration of temporal responsibility, how the Doctor sees himself after he assumes the ‘Victorious’ label, and how cocky and sassy he can be. For reference on that specific character trait, listen to Big Finish’s Victorious trilogy featuring the Eighth Doctor.

The Time Marshal obviously wants the Doctor out of her way, but once his mouth is open then people are listening, and he uses the gift of the gab to delay Galaxy L-10’s fate at the hands the time-locking 30-metre tall hourglass. At one point, the Time Marshal becomes so frustrated that she wants to time-lock the Doctor too.

It’s at this point where, after a very nice musical interlude once the Doctor seems to be removed from the action by the Time Marshal, the story turns from set-up into delivery upon delivery of the plot points that have been building up.

The interlude is used handily to show a passing of time before the listener is returned to the action with a Doctor firing on all cylinders. While it’s Neve McIntosh reading The Shattered Hourglass, it’s written and delivered as if it were David Tennant springing around the scenery on set.

The story gets stronger and stronger as it goes on, and feels very much like a piece of 20th Century science-fiction – in a good way, as if it were from TV Comic – while also tying in brilliantly to the Tenth Doctor’s television run. The pièce de résistance is the final reveal of the 35-minute tale, which has the Doctor wandering off with a grin on his face and leaving the listener with the same. A recommended buy.

Download The Shattered Hourglass from Big Finish for just £2.99.